65 lines
1.5 KiB
Rust
65 lines
1.5 KiB
Rust
// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// Test how overloaded deref interacts with borrows when only
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// Deref and not DerefMut is implemented.
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use std::ops::Deref;
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struct Rc<T> {
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value: *const T
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}
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impl<T> Deref for Rc<T> {
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type Target = T;
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fn deref<'a>(&'a self) -> &'a T {
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unsafe { &*self.value }
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}
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}
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fn deref_imm(x: Rc<isize>) {
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let __isize = &*x;
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}
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fn deref_mut1(x: Rc<isize>) {
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let __isize = &mut *x; //~ ERROR cannot borrow
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}
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fn deref_mut2(mut x: Rc<isize>) {
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let __isize = &mut *x; //~ ERROR cannot borrow
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}
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fn deref_extend<'a>(x: &'a Rc<isize>) -> &'a isize {
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&**x
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}
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fn deref_extend_mut1<'a>(x: &'a Rc<isize>) -> &'a mut isize {
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&mut **x //~ ERROR cannot borrow
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}
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fn deref_extend_mut2<'a>(x: &'a mut Rc<isize>) -> &'a mut isize {
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&mut **x //~ ERROR cannot borrow
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}
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fn assign1<'a>(x: Rc<isize>) {
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*x = 3; //~ ERROR cannot assign
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}
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fn assign2<'a>(x: &'a Rc<isize>) {
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**x = 3; //~ ERROR cannot assign
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}
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fn assign3<'a>(x: &'a mut Rc<isize>) {
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**x = 3; //~ ERROR cannot assign
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}
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pub fn main() {}
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